Narelle Towie, Perth Now 30 Apr 09;
POPULATIONS of the world's largest fish, the whale shark, are increasing at WA's Ningaloo Reef, scientists report.
Researchers made the discovery using an online photo-identification technology called ECOCEAN which they used to track the sharks around the world.
The system works by encouraging members of the public to submit photos of whale sharks to the library’s database.
Scientists then identify the fish using pattern-recognition software which is then used to illustrate the whale sharks migratory habits.
More than 500 new whale sharks, considered vulnerable, have been discovered at Ningaloo reef since the project first began in 1993.
The team’s findings have been published in the journal Endangered Species Research (ESR).
Whale sharks migrate up to 12,000km and prior to the 1980s there had been only 350 confirmed sightings of the giant fish.
In some countries whale sharks are still harvested commercially.
Lead author on the ESR study Jason Holmberg says smaller whale sharks have also been discovered feeding at the reef during the study.
“Why are more and more juveniles arriving on the reef? It’s unclear, but it’s positive news,” Mr Holmberg said.
Founder of the ECOCEAN whale shark project and Murdoch University scientist Brad Norman says the research shows that whale sharks can increase where they are well-protected.
“We have also demonstrated the power of citizen-science, that ordinary people around the world can make a real contribution to serious research and conservation.”
“Thanks to increasing levels of data collection, we’re finally able to estimate how many whale sharks appear annually, how long they typically remain at Ningaloo Marine Park (NMP), their patterns of arrival and departure and shifts in their population structure,” he said.
Mr Norman recently discovered that whale sharks swim much faster than thought, nose-diving to the ocean floor for food and using their enormous weight and gravity for speed.
Curtin University researchers have also showed that whale shark ecotourism is a boon for local communities.
“Our results indicate that without whale sharks at Ningaloo Marine Park (NMP) up to $4.6 million would be lost from the local economy,” Mr Norman said.
“Similar economic benefits could be available at other whale shark ‘hotspots’ around the world,” he said.
The researchers hope now to use this technology to analyse data from other study sites and obtain a broader picture of the species.
Mr Norman warns that fundamental information on the whale sharks remains a mystery.
“Of over 1300 whale sharks we have tagged with our partners in the Indian and Pacific Oceans, very few have been sighted at other study locations, even though some whale sharks have been tracked for thousands of kilometres,” Mr Norman says.
He also cautions against making assumptions of how this may affect broader Indian Ocean populations, especially considering the migratory nature of whale sharks.
”Our models provide information only about the whale sharks visiting the northern region of NMP annually. While the number of sharks returning to that area in multiple seasons appears to be growing, we cannot make assumptions of how this may affect broader Indian Ocean populations, especially considering their migratory nature,” he said.
The success of the online survey has prompted scientists to issue a worldwide call to holiday-makers and divers to join in a global effort to monitor and protect the largest fish in the sea - thought to be at risk in the waters off many countries.
For further information on whale sharks visit www.whaleshark.org or call Earthwatch on 03 9682 6828.
Tourists help save whale sharks
ECOCEAN on ScienceAlert 1 May 09
Numbers of the whale shark ‐ the world's largest fish and one of its rarest – are steady and may even be increasing in one of its vital habitats, a revolutionary study by scientists and the general public has revealed.
The remarkable success of the online survey of whale sharks carried out by Earthwatch volunteers, tourists, divers and researchers at Ningaloo, WA has prompted scientists to issue a worldwide call to holiday makers and divers to join in a global effort to monitor and protect the largest fish in the sea - thought to be at risk in the waters off many countries.
"Besides showing that whale sharks can increase where they are well-protected, we have also demonstrated the power of citizen-science, that ordinary people around the world can make a real contribution to serious research and conservation," says Brad Norman, Project Coordinator and who founderd of the ECOCEAN whale shark project.
ECOCEAN, a not-for-profit group with offices in Australia and USA, has pioneered this new program – aimed at engaging members of the public to help monitor and ultimately protect wildlife - both in the sea and potentially recently on land through the development of similar programs for other endangered species.
“Thanks to increasing levels of data collection,” saysid Project Coordinator Brad Norman, “we’re finally able to estimate how many whale sharks appear annually, how long they typically remain at Ningaloo Marine Park (NMP), their patterns of arrival and departure, and shifts in their population structure.”
The team’s new findings have been published in the journal Endangered Species Research (ESR) and Jason Holmberg, lead author on the ESR study states that “Using an unprecedented number of photographs and video collected from the public and from the dive industry at NMP, we have been able to create statistical models demonstrating a modestly increasing annual population of around 150 sharks. We’re also seeing an increase in the number of smaller whale sharks feeding at the reef and returning in subsequent years. Why are more and more juveniles arriving on the reef? It’s unclear, but it’s positive news.”
This study complements a collaborative study with Curtin University, Western Australia, the results of which were published this month in the Journal of Ecotourism (JE), acknowledging the whale shark ecotourism industry as a boon for local communities working to protect this threatened species.
“Our results indicate that without whale sharks at NMP, up to AUD 4.7 6 million would be lost from the local economy” notes Norman “and similar economic benefits could be available at other whale shark ‘hotspots’ around the world. Therefore, providing it is well-managed, this form of non-consumptive exploitation should continue to be promoted as a sustainable alternative to unsustainable hunting of this threatened species”.
The team’s findings and techniques are useful beyond Western Australia. “For the first time, our recent study demonstrates a set of population models that can be expanded to incorporate other whale shark aggregations in the Indian Ocean if and when sharks can be linked between them.” saysid Mr. Holmberg.
“We are constructing a regional research framework. Community monitoring using the ECOCEAN Library has recorded more than 500 individual whale sharks visiting NMP since the industry began in 1993. A related study in the Philippines in collaboration with WWF has so far recorded 250 individual animals there, while another in Mozambique, conducted by the Manta & Whale Shark Research Centre, has confirmed sightings of more than 350 identified individuals.
Data from Ningaloo represent only a snapshot of the migrations of these sharks, but it’s a significant, long-term baseline. Moving forward, we can now begin to cooperatively integrate and analyze data from other study sites and obtain a broader picture of the species. For such a long-lived, far-ranging animal, a big-picture view is important – especially to promote global protection. It is important to note that the whale shark is still considered ‘vulnerable to extinction’, and with such a small population, continuing caution and protection is imperative.”
However, the research team notes that despite the sophisticated tools pioneered at Ningaloo, some fundamental mysteries remain.
“There is still a large amount of mystery surrounding these sharks, and there remains a fair amount of fundamental exploration ahead. Of over 1,300 whale sharks we have tagged with our partners in the Indian and Pacific Oceans, very few have been sighted at other study locations, even though some whale sharks have been tracked for thousands of kilometers. We couldn’t conduct our research on any meaningful scale without the public’s help,” saysid Mr. Norman, “and we’re looking forward to a continued partnership with ecotourism at Ningaloo and elsewhere to take this project forward.”
ECOCEAN (USA) President Dr Zaven Arzoumanian notes that “Without the direct contribution of data by the public, we would never have been able to perform our analysis and get such an in-depth look at the whale sharks of Ningaloo. Tourists and tour operators there are part of a small army of individuals collecting and sharing data globally for the species. Our framework at www.whaleshark.org supports collaborative research and provides the public with the opportunity to view and contribute data. They can also contribute home computing power to our grid computer at www.sharkgrid.org, in a similar way to the SETI@home (Search for ExtraTerrestrial Intelligence) project. This allows even those who have never seen a whale shark to help protect them by participating in a global, online research community.”
